The Touch Project

Ok,

There will be tons of new stuff here…

1. some pics of the 3d model (part of an animated movie that will be soon uploaded u can see its’ first part below..), showing our Multitouch table.

2.pics of the construction and estimated size of the whole project.

3.After several hours of adjusting, calibrating, we finally managed to calibrate the display ( with about 95% acuraccy) the other 5 % will be there when we finish building the first wood prototype ).

We will put some videos of the current status

Enjoy!

3d Model of the project- (with different textures)- Made in ‘Maya’ :

2. some pics of the project ( and how this messed up prototype looks now)

note that we don’t use this GIGANTIC projector no more..

we got ourselves a new Benq tiny DLP projector that fits in perfectly!

3. some videos of our last session,

testing with apps from touchlib, and Laurence Muller:

Piano app:

Media App:

The last update was posted about 2 months ago.

In that time we’ve checked for materials to cover the surface with in orderto enhance the touch tracing on the surface.

We’ve checked it with thin sketch paper, thick (120g) sketch paper and according to advice we’ve gotte from few NUI groups users, we’ve tried using the Rosco rear projection film (available at the “Rosebrand” company, they ship worldwide).

Both sketch papers didn’t give us the results we were hoping for. The camera caught the paper as a static disturbance and showed static snow on the screen. Once we’ve touched it it enhanced the touch tracing, but the apps we’ve tried to check it with just collpased since the static caused it to detect too many touch points on the surface.

So we’ve tried the rosco which worked perfectly….until we’ve touched it.

The Rosco rear projection film covers the surface completely and without causing the camera to see static noise.

It enhances the touch points, but the problem is that there’s a trace that’s left on the rosco for about 10-15 seconds.

Apps worked while the Rosco was on the surface, but the trace caused a delay in the applicaions’ response time.

So we had to go with the thing we’ve tried to avoid - Silicone rubber layer.

The silicone rubber layer is a layer that covers the surface and creates a flexible silicone layer on it. The silicone, once dried and ready, becomes flexible - when you touch it bounces back up.

The silicone creates a moist enviorment on the surface, hence enhancing the touch points so they’re clearly seen on the webcam even if you don’t press you finger strongly against the surface.

The recommended silicone is “Sorta-clear 40″, 40 represents the “shor” level. As low as the shor number is - the more flexible it’ll turn out once the silicone dries.

We’ve got a 1kg can of silicone

50mg of thinner

50mg of silicone hardner.

Usually you’ll get directions for using the silicone and how to figure out the right amounts you’ll have to mix.

We’ve used:

200g of silicone rubber

20mg of thinner

20mg of hardner

As you can see, we’ve used an electronic scale to find the accurate measures needed of each material.

We’ve also got 3 U shaped aluminum profiles - 2 to hold the perspex in them and create the space needed for the layer on top of the surface, and 1 more to flatten the layer once it was poured on the surface.

First of all mix the thinner with the silicone. Stir in it slowly for about 3-5 minutes. If you’re getting a lot of tiny bubbles inside your silicone, don’t be alarmed - you can flatten them out while you pour it on the plexiglass surface.

 Just so what we’ve wrote here won’t sound like chinese:

This is the silicone in the original can - smooth and bubble free.

 This is the silicone after we’ve mixed it with the thinner for about 3-5 minutes - full of tiny bubbles (again - no fear, they’re easily flattened once the silicone is poured on the surface).

Once done mixing the thinner, add the hardner. You have 15 minutes before it starts working, so mix it all good once more and pour it on the surface.

In order to flatten the bubbles we’ve used the back side of plastic spoons.

Once we flattened all of them, we’ve used an aluminm profile to flatten the layer over the surface. The silicone came all smooth and clear after 3-4 strokes with the aluminum profile.

We’ve covered it up with paper and towels so dust won’t get in and left it to dry for 48 hours.

The result was stunning, the silicone was hard but flexible, it came out just the way we needed it to be.

NEXT TIME ON: Operation Multitouch!

We’ve got a DLP projector, and with the silicone layer and Rosco film ready, we’re about to make our first attempt on projecting and using the surface!

Stay tuned….

This post will be dedicated to the frustration and despair that follow an unsuccessful session.

The last post shows the L.E.Ds all lighted up, after we’ve plugged them into an electricity point.

The wiring we did was temporary, so wee got together again, all happy to keep up our good work, and bought those rectangle shaped plastic connectors

As you can see - these have to entrance points. Use a screwdriver to open the screw on top of the connector, insert a wire

(or in our case - the L.E.D’s leg, like that

)

and screw the screw back into place (Man that’s a wierd sentence).

We’ve decided to use these connectors in order to replace our shaky temporary wiring, to a more stable and better looking one.

So we took our old wiring apart, wire by wire, replacing each with a plastic connector.

NOTE: The L.E.D diagram was very useful in this part too, since we lost track of the wiring a time or two, so always keep that diagram close to you while changing any part of the wiring. You can find the diagram in the “Let there be light!” post.

Once we were done, we’ve got this FINE PIECE OF WORK! and got very proud of ourselves.

As shown in the picture above, we’ve also drilled holes in the frames’ corners, so we’ll be able to attach them together using these L shaped metal parts.

Looking good eh? You bet is does!

So, what are we waiting for? Let’s plug it in again!

Well, dear readers, did you really think that everything will go as smooth as planned? Then you have to read this posts’ title again because this is the part where things got wrong.

As we plugged the frame back into the electricity point, we saw that a section of the L.E.Ds at one corner did not light up.

Furthermore - While trying to place the perspex inside the frame, we’ve noticed the the bolts that hold the L shaped pieces (hence, holding the frame attached together), block the perspex from fitting in the frame the way we’ve intnded it to.

In other words - the bolts are too big and the perspex was sticking out of the frame in a way that didn’t allow us to close the frame completely, with the perspex placed in.

Well, one problem at a time.

We’ve decided to get rid of the current L shaped pieces and replace them with differnet kind of….Yep, L shaped pieces, but this time we’ve gotten smart and went for the external kind of pieces.

These pieces hold the frame together from the L.E.Ds side (the exterior of the frame). The bolts used to put this pieces on the frame are no bigger then one of our LED lights, which doesn’t block the perspex from fitting in perfectly in the frame, just like G-D and of course - we’ve intended.

Well, you can take god off this thing, I don’t really think that he cares for MultiTouch surfaces, after all he’s got the ultimate MT Thingy, doesn’t he? He calls it “the universe” and I’m just mumbling nonsense here.

Ok, so we’ve got the new pieces to hold the frame, problem #1 is over.

Now, the main problem - What’s up with the wiring?! How comes that an entire section doesn’t work?

Let’s check it out, shall we?

We’ve grabbed the diagram and got into checking each and every conncetor. Here and there we’ve come across a wire that slipped out or a LED that didn’t fit in too well.

Pleased with our quick troubleshooting procedure, we plugged the surface back in and… Still not working!!!

So, relaxed as we were (relaxed, yeah right….steam had started to come out of our ears) we’ve double checked…again.

and again

and…..again!

Finally we’ve seen a resistor and one LED that’d slipped out of one connector.

So we’ve attended the delicate situation with maximum care when…..

AWWWWW MANNNNN IT BROKEEEEEEEE!!!!

Damn, now what do we do? Oh, of course, we’ still have one LED to fix.

So with one broken resistor and an encouraged spirit we’ve attended the LED.

we’ve gotten the connectors’ screw open when ….*SNAP!*….

As the famous saying goes - a picture is worth a thousan words. So here’s the picture, now, instead of a thousand words imagine 1000 swears. Yep, that’s our situation!

Let’s just say that the LED snaping, closed that work session.

We’ve called it the day and went chasing pigeons.

When the sun came out the next day, we bought some more LED lights, resistors and anti-depressant medication, and got back to work.

With the LED diagram at hand again, and with a lot of patience, we’ve managed to re-wire everything, bolt the frame back together with the perspex placed inside and got to the moment of truth again.

Allow me to become a redneck for a moment:

Folks, we’ve never known happiness like the one we’ve known when that surface came lightin’ all up, man, when we fir’d up that hotdamn thing we went loony as a toon, diggity damn

And back to my normal self -

When the LEDs were lit, we were back in bussiness again -

without spending another moment we’ve grabbed the webcam, the laptop and a couple of chairs, and placed them in this order:

as you can see, the camera is placed underneath the surface, so it can “see” the LED’s light-grid, the surfae itself is placed between 2 chairs, simulating approximately the height we want it to actually be.

The next few lines will be detailed in future posts, but here’s a rough description:

With the webcam connected to the laptop and the surface plugged in to elctricity, we’ve activated the “smoke” application and tried touching the surface, in order to produce somke trails.

Yeah , it worked and we’ve opened a bottle of our finest 1883 coca cola! (well, it was a 2008 one but you catch our drift here )

the next stages will be:

1. Calibrating the camera and surface , so it will be accurate (at the moment we’ve got resolution difference so while touching the top right corner of the surface, the smoke trail appears near the middle of the screen)

2. Trying to work with a media application, such as Laurence Muller’s picture resizing application (can be found at his blog - www.multigesture.net, thanks Laurence for all the support!)

3. Buying Bob Dylan’s “Live in Bodukan” or Roy Orbisons’ “Black and white night” cd’s , but that has nothing to do with this blog

That’s all folks and remember - Do not give in to despair, hard work and double checking pays off, as well as a lot of patience!

Feel free to ask us any questions.

Roey & Itamar.
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